4 Easy Methods for Dehydrating Tomatoes at Home

If you have a bountiful summer harvest of tomatoes from your garden, you can use one of several methods to dehydrate tomatoes and preserve them for later use.

How to Dehydrate Tomatoes at Home

Dehydrating tomatoes under the Sun

You need certain conditions for efficiently dehydrating tomatoes under the sun. You need good air circulation, consistently high temperature of 90ºF or higher, and low humidity (lower than 60%). If you don’t have these conditions in the place where you live, it is better to opt for another method for dehydrating tomatoes.

Procedure:

Choose tomatoes that are uniform in size so you get even results. Wash the tomatoes. Dry them thoroughly.

You have the option of removing the skin. Use a knife to make an X cut on the bottom of each tomato. Cut just deep enough to break the skin. Blanch the tomatoes in boiling water for about 30 seconds. Take the tomatoes out of the pot using a slotted spoon. Immediately transfer the tomatoes to a pot of ice-cold water. You can then easily take the skin off.

Here is a nice video about how to blanch tomatoes.

Core the tomatoes and take out the ends. If you are using cherry tomatoes, cut them in half. If you are using Roma tomatoes, cut them in quarters or halves. If you are using regular slicing tomatoes, slice them into ¼” wedges.

You have the option of seeding the tomatoes. Using your finger or a spoon, scoop the seeds out, leaving only the pulp. Use a paper towel for blotting superfluous juice.

After all the preparations are done, you are ready to start the dehydration process.

Put the tomatoes with their cut sides up on plastic, wooden, or non-stick drying racks. (Don’t use trays with galvanized metal screening to avoid having the acid content of the tomatoes interact with the material).

You have the option of dusting the tomatoes with garlic powder, salt, and fresh herbs of your choice.

Put the racks directly under the sun outdoors. Lay them on raised boards to ensure that the air circulates freely above and below the racks. Avoid stacking the racks.

Use wooden skewers to suspend a piece of cheesecloth or netting over the tomatoes to keep insects off. Don’t put the cloth directly on the tomatoes as this will hinder proper ventilation.

Turn the tomatoes once or twice a day.

Take the tomatoes indoors at night to keep the dew off. You can leave the tomatoes outdoors if you have a shed and if it doesn’t get too cold outside.

Inspect the tomatoes for dryness after about 4 days.

The tomatoes will be suitably dehydrated between 4 days and 2 weeks. The length of drying time will depend on certain factors including the thickness of slices, the juiciness of the tomatoes, humidity, and outdoor temperature.

Dehydrating tomatoes in a food dehydrator

Most experts agree that using a food dehydrator is the best and easiest option for dehydrating tomatoes.

A food dehydrator gives you consistent results. Most dehydrators have a thermostat for regulating temperature so that the tomatoes can dry evenly. It has a small fan or blower that helps the air circulate efficiently. It also often comes with a timer.

Using a food dehydrator also has other advantages. You can dehydrate tomatoes even if the climate isn’t sunny. You can use the equipment in the garage, terrace, or anywhere in the house that has an electric outlet.

Procedure:

Pre-heat your food dehydrator to 135º-140ºF. (If your dehydrator does not come with a thermostat, you can use a cooking thermometer placed on the bottom tray).

Prepare the tomatoes as outlined in the previous paragraph. (dehydrating tomatoes under the Sun)

Lightly coat your dehydrator trays with vegetable spray. You also have the option of rubbing the trays with some olive oil so that the tomatoes don’t stick to the tray.

Put the sliced tomatoes on the dehydrator trays. The cut sides should face up. Put the slices half an inch apart to prevent them from touching each other.

You can use a sprinkling of herbs, garlic powder, and salt for taste.

See to it that there is enough space (1 or 2 inches) between racks so that that the air can circulate properly.

Rotate the racks as needed so that the tomatoes can dry evenly.

Check the tomatoes every now and then. If some slices become dry before the rest, take them out so that they don’t get scorched.

Expect the tomatoes to be properly dehydrated after 8 to 12 hours. Dried tomatoes will look leathery and shriveled (but not tacky). They would have reduced in size. Take them out of the dehydrator and let them cool completely.

Dehydrating tomatoes in an oven

Whether you use a food dehydrator or an oven for dehydrating tomatoes, you enjoy the same advantages. You don’t have to wait for sunny weather to work on your tomatoes. You can control the temperature of your oven.

Procedure:

Preheat your oven to either 200ºF or the lowest setting.

Use the same preparation procedure as described before.

Take note of the following:

Use slotted trays or cake racks so you get better air circulation. Don’t dry your tomatoes on baking trays or cookie sheets that have no slots; the tomatoes won’t dehydrate evenly.

If you are using 2 or more trays, rotate the trays every couple of hours so the tomatoes will dry evenly. Check the tomatoes regularly to see if they’re done.

Take note of baking times. Cherry tomatoes will require between 3 to 4 hours. Roma tomatoes will take between 4 to 8 hours. Standard slicing tomatoes will take between 8 to 12 hours, depending on how big the tomatoes are.

Dehydrating tomatoes in a microwave oven

Using a microwave oven for dehydrating tomatoes can be more challenging than the other methods already discussed. However, it can be done – provided you take note of several key elements:

See to it that you use a low power level.

Avoid the temptation of zapping the tomatoes on “High.”

Don’t use a microwaveable plate or a paper towel. Use a microwave-safe bacon rack or any similar tray with ribs to allow sufficient air circulation.

Dry a smaller batch of tomatoes at a time. For example, dry between 7 to 10 Roma tomatoes at a time.

Cook the tomatoes for longer periods.

Monitor the tomatoes closely.

Procedure:

Use the same preparatory steps outlined before.

In a microwave oven with 10 power levels, use Power Level 2. Cook the tomatoes for about 45 minutes. Turn the tomatoes every 15 minutes. (Depending on the model of your microwave, adjust setting and cooking time).

Change the Power Level to 1 and cook the tomatoes in 5-minute increments, pausing to turn the tomatoes after each interval, until the tomatoes are properly dehydrated.